Operation Manual of INVT CHS100 AC Servo Drive 7 Gain adjustment
102
Fig. 7-1 Block diagram of position control
The general procedures for parameter adjustment in the position mode are:
1) Initial setting of the parameters
The defaults of the parameters can be recovered by the default parameter recovering
operation (see chapter 5.2.4 for details).
2) Adjustment of the gain of the position loop
When the servo motor is running with default parameters, if the system oscillation
occurs with buzz, the position gain (Pb.01 or Pb.06) should be adjusted smaller. If the
system rigidity is relatively small, the position gain should be adjusted larger.
3) Adjustment of the position smoothing filter
During position control, if the position pulse command input frequency varies largely, it
may be caused by a larger impulse. At this time the position smoothing filter time
constant (Pb.11) should be adjusted to moderate the impulse.
4) Adjustment of the electronic gear
If the pulse transmission frequency of the pulse generator is restricted, or the
transmission frequency does not meet the mechanical requirements, we can change
the pulse input frequency by adjusting the value of the electronic gear parameters
(PA.04, PA.05, etc.) to meet the requirements for position control.
5) Adjustment of position feed-forward
In the case the retention pulse is large or fault-free follow-up is required, we can
improve the position follow-up performance by adjusting the position feed-forward gain
parameter (Pb.02) and position feed-forward gain filter parameter (Pb.03). However, it
should be noted that if the position feed-forward gain is too large, it may cause system
oscillation.
Position
Command
Position
smoothing
filter
Electroni
c gear
Encoder
frequency
division
Position
feed-forward
Position
controller
Low-pass
filter
Trap filter
Speed
controller
Speed test
filter
Torque
controller
Encoder
Motor